This invention relates to medical devices for injecting living bodies and, more particularly, to a single-use hypodermic syringe which locks up after one use comprising, a body having a cylindrical container for holding a fluid; a hollow needle communicating with an interior of the cylindrical container through one end thereof; a sliding plunger disposed in the cylindrical container; a plunger rod communicating with the sliding plunger through an opposite end of the cylindrical container; and, locking means for allowing the sliding plunger to move only in a direction towards the one end whereby after the plunger is moved adjacent the one end, it cannot be withdrawn for subsequent use.
Not so very long ago, hypodermic syringes were of metal and glass. Their use was complicated by the fact that they had to be sterilized between uses as by autoclaving. Recent developments in plastics have made a cheap, disposable syringe for intended single use a practicality. Use of cheap, disposable carpules in a hypodermic syringe holder also offer decided advantages. Since only the carpule and the needle need to be completely sterile, only those parts are replaced in the holder for multiple uses.
The heavy illegal use of injected drugs along with the proliferation of diseases such as hepatitis B and AIDS borne in the body fluids has created a problem where one previously did not exist. Diabetics, hemophiliacs, and the like, employing self-use, disposable needle devices could simply dispose of the devices without fear that they would be put to illicit use. Now, however, there is a need for a way to make such devices truly one-time devices and prevent their subsequent use--without unduly increasing the cost or convenience to the legal users thereof.
Wherefore, it is the object of this invention to provide a way to make disposable and carpule type syringes truly one-time devices and to lock them after first use from any subsequent use.
Other objects and benefits of the invention will become apparent from the detailed description which follows hereinafter when taken in conjunction with the drawing figures which accompany it.